<template>
    <div class="player" v-show="playlist.length>0">
        <transition name="normal"
                    @enter="enter"
                    @after-enter="afterEnter"
                    @leave="leave"
                    @after-leave="afterLeave"
        >
            <div class="normal-player" v-show="fullScreen">
                <div class="background">
                    <img width="100%" height="100%" :src="currentSong.image">
                </div>
                <div class="top">
                    <div class="back" @click="back">
                        <i class="icon-back"></i>
                    </div>
                    <h1 class="title" v-html="currentSong.name"></h1>
                    <h2 class="subtitle" v-html="currentSong.singer"></h2>
                </div>
                <div class="middle"
                     @touchstart.prevent="middleTouchStart"
                     @touchmove.prevent="middleTouchMove"
                     @touchend="middleTouchEnd"
                >
                    <div class="middle-l" ref="middleL">
                        <div class="cd-wrapper" ref="cdWrapper">
                            <div class="cd" :class="cdCls">
                                <img class="image" :src="currentSong.image">
                            </div>
                        </div>
                        <div class="playing-lyric-wrapper">
                            <div class="playing-lyric">{{playingLyric}}</div>
                        </div>
                    </div>
                    <scroll class="middle-r" ref="lyricList" :data="currentLyric && currentLyric.lines">
                        <div class="lyric-wrapper">
                            <div v-if="currentLyric">
                                <p ref="lyricLine"
                                   class="text"
                                   :class="{'current': currentLineNum ===index}"
                                   v-for="(line,index) in currentLyric.lines">{{line.txt}}</p>
                            </div>
                        </div>
                    </scroll>
                </div>
                <div class="bottom">
                    <div class="dot-wrapper">
                        <span class="dot" :class="{'active':currentShow==='cd'}"></span>
                        <span class="dot" :class="{'active':currentShow==='lyric'}"></span>
                    </div>
                    <div class="progress-wrapper">
                        <span class="time time-l">{{format(currentTime)}}</span>
                        <div class="progress-bar-wrapper">
                            <progress-bar :percent="percent" @percentChange="onProgressBarChange"></progress-bar>
                        </div>
                        <span class="time time-r">{{format(currentSong.duration)}}</span>
                    </div>
                    <div class="operators">
                        <div class="icon i-left" @click="changeMode">
                            <i :class="iconMode"></i>
                        </div>
                        <div class="icon i-left" :class="disableCls">
                            <i @click="prev" class="icon-prev"></i>
                        </div>
                        <div class="icon i-center" :class="disableCls">
                            <i @click="togglePlaying" :class="playIcon"></i>
                        </div>
                        <div class="icon i-right" :class="disableCls">
                            <i @click="next" class="icon-next"></i>
                        </div>
                        <div class="icon i-right">
                            <i class="icon" @click="toggleFavorite(currentSong)"
                               :class="getFavoriteIcon(currentSong)"></i>
                        </div>
                    </div>
                </div>
            </div>
        </transition>
        <transition name="mini">
            <div class="mini-player" v-show="!fullScreen" @click="open">
                <div class="icon">
                    <img :class="cdCls" width="40" heoght="40" :src="currentSong.image">
                </div>
                <div class="text">
                    <h2 class="name" v-html="currentSong.name"></h2>
                    <p class="desc" v-html="currentSong.singer"></p>
                </div>
                <div class="control">
                    <progress-circle :radius="radius" :percent="percent">
                        <i @click.stop="togglePlaying" class="icon-mini" :class="miniIcon"></i>
                    </progress-circle>
                </div>
                <div class="control" @click.stop="showPlaylist">
                    <i class="icon-playlist"></i>
                </div>
            </div>
        </transition>
        <playlist ref="playlist"></playlist>
        <audio ref="audio" :src="currentSong.url" @play="ready" @timeupdate="updateTime" @ended="end"></audio>
    </div>
</template>


<script type="text/ecmascript-6">
  import {mapGetters, mapMutations, mapActions} from 'vuex'
  import animations from 'create-keyframe-animation'
  import {prefixStyle} from 'common/js/dom'
  import ProgressBar from 'base/progress-bar/progress-bar'
  import ProgressCircle from 'base/progress-circle/progress-circle'
  import {playMode} from 'common/js/config'
  import {shuffle} from 'common/js/util'
  import Lyric from 'lyric-parser'
  import Scroll from 'base/scroll/scroll'
  import Playlist from 'components/playlist/playlist'
  import {playerMixin} from 'common/js/mixin'

  const transform = prefixStyle('transform')
  const transitionDuration = prefixStyle('transitionDuration')

  export default {
    mixins: [playerMixin],
    name: "player",
    data() {
      return {
        songReady: false,  //当歌曲加载时是否可操作  默认false
        currentTime: 0,
        radius: 32,
        currentLyric: null,
        currentLineNum: 0,
        currentShow: 'cd',
        playingLyric: ''
      }
    },
    computed: {
      cdCls() {
        return this.playing ? 'play' : 'play pause'
      },
      playIcon() {
        return this.playing ? 'icon-pause' : 'icon-play'
      },

      miniIcon() {
        return this.playing ? 'icon-pause-mini' : 'icon-play-mini'
      },
      disableCls() { //当歌曲加载时 设置一个css属性disable
        return this.songReady ? '' : 'disable'
      },
      percent() {
        return this.currentTime / this.currentSong.duration  //当前播放的时间 除以总时长
      },
      ...mapGetters([
        'fullScreen',
        'playing',
        'currentIndex',
      ])
    },
    created() {
      this.touch = {}
    },
    methods: {
      //错误做法： this.fullScreen = false
      //正确做法： 通过mapMutations写入
      back() {
        this.setFullScreen(false)
      },
      open() {
        this.setFullScreen(true)
      },
      //事件钩子: 创建CSS3动画
      enter(el, done) {
        const {x, y, scale} = this._getPosAndScale()
        let animation = {
          0: {
            transform: `translate3d(${x}px,${y}px,0) scale(${scale})`
          },
          60: {
            transform: `translate3d(0,0,0) scale(1.1)`
          },
          100: {
            transform: `translate3d(0,0,0) scale(1)`
          }
        }
        animations.registerAnimation({
          name: 'move',  //动画名称
          animation,
          presets: {
            duration: 400,  //动画间隔
            easing: 'linear'  //晃动 // linear 线系
          }
        })
        animations.runAnimation(this.$refs.cdWrapper, 'move', done)  //注册动画 done 回调函数
      },
      afterEnter() {
        animations.unregisterAnimation('move')
        this.$refs.cdWrapper.style.animation = ''  //清空动画
      },
      leave(el, done) {
        this.$refs.cdWrapper.style.transition = 'all 0.4s'
        const {x, y, scale} = this._getPosAndScale()
        this.$refs.cdWrapper.style[transform] = `translate3d(${x}px,${y}px,0) scale(${scale})`
        this.$refs.cdWrapper.addEventListener('transitionend', done)
      },
      afterLeave() {
        this.$refs.cdWrapper.style.transition = ''
        this.$refs.cdWrapper.style[transform] = ''
      },
      //控制播放状态
      togglePlaying() {
        if (!this.songReady) {
          return
        }
        this.setPlayingState(!this.playing)
        if (this.currentLyric) {
          this.currentLyric.togglePlay() //歌词切换播放暂停
        }
      },
      end() {
        if (this.mode === playMode.loop) {
          this.loop()
        } else {
          this.next()
        }
      },
      loop() {
        this.$refs.audio.currentTime = 0
        this.$refs.audio.play()
        if (this.currentLyric) {
          this.currentLyric.seek(0) //歌词偏移到一开始
        }
      },
      //上一首
      prev() {
        if (!this.songReady) {  //当歌曲加载时,禁止操作
          return
        }
        if (this.playlist.length === 1) { //只有一首歌，单曲循环
          this.loop()
          return
        } else {
          let index = this.currentIndex - 1
          if (index === -1) {
            index = this.playlist.length - 1
          }
          this.setCurrentIndex(index)
          if (!this.playing) {
            this.togglePlaying()
          }
        }
        this.songReady = false
      },
      //下一首
      next() {
        if (!this.songReady) {  //当歌曲加载时,禁止操作
          return
        }
        if (this.playlist.length === 1) { //只有一首歌，单曲循环
          this.loop()
          return
        } else {
          let index = this.currentIndex + 1
          if (index === this.playlist.length) {
            index = 0
          }
          this.setCurrentIndex(index)
          if (!this.playing) {
            this.togglePlaying()
          }
        }
        this.songReady = false
      },
      ready() {
        this.songReady = true
        this.savePlayHistory(this.currentSong)
      },
      error() {
        this.songReady = true  //当歌曲发生错误 设置songReady 为true
      },
      updateTime(e) {
        this.currentTime = e.target.currentTime
      },
      format(interval) {
        interval = interval | 0
        const minute = interval / 60 | 0
        const second = this._pad(interval % 60) //this._pad 补零
        return `${minute}:${second }`
      },
      onProgressBarChange(percent) {
        const currentTime = this.currentSong.duration * percent
        this.$refs.audio.currentTime = currentTime
        if (!this.playing) {
          this.togglePlaying()
        }
        if (this.currentLyric) {
          this.currentLyric.seek(currentTime * 1000)  //偏移歌词到拖动时间的对应位置
        }
      },

      //获取解析后的歌词
      getLyric() {
        this.currentSong.getLyric().then((lyric) => {
          if (this.currentSong.lyric !== lyric) {
            return
          }
          //实例化lyric对象
          this.currentLyric = new Lyric(lyric, this.handleLyric)
          //  console.log(this.currentLyric)
          if (this.playing) {
            this.currentLyric.play()
          }
        }).catch(() => {
          //请求失败，清理数据
          this.currentLyric = null
          this.playingLyric = ''
          this.currentLineNum = 0
        })
      },
      handleLyric({lineNum, txt}) {
        this.currentLineNum = lineNum
        if (lineNum > 5) {
          let lineEl = this.$refs.lyricLine[lineNum - 5] //保证歌词在中间位置滚动
          this.$refs.lyricList.scrollToElement(lineEl, 1000)
        } else {
          this.$refs.lyricList.scrollTo(0, 0, 1000)//滚动到顶部
        }
        this.playingLyric = txt
      },
      //歌词滑动
      middleTouchStart(e) {
        this.touch.initiated = true //初始化标志位
        const touch = e.touches[0]
        this.touch.startX = touch.pageX
        this.touch.startY = touch.pageY
      },
      middleTouchMove(e) {
        if (!this.touch.initiated) {
          return
        }
        const touch = e.touches[0]
        const deltaX = touch.pageX - this.touch.startX
        const deltaY = touch.pageY - this.touch.startY
        //维护deltaY原因：歌词本身Y轴滚动，当|deltaY| > |deltaX|时，不滑动歌词
        if (Math.abs(deltaY) > Math.abs(deltaX)) {
          return
        }
        const left = this.currentShow === 'cd' ? 0 : -window.innerWidth
        const offsetWidth = Math.min(0, Math.max(-window.innerWidth, left + deltaX))
        this.touch.percent = Math.abs(offsetWidth / window.innerWidth)
        //滑入歌词offsetWidth = 0 + deltaX(负值)  歌词滑出offsetWidth = -innerWidth + delta(正值)
        this.$refs.lyricList.$el.style[transform] = `translate3d(${offsetWidth}px, 0, 0)`
        this.$refs.lyricList.$el.style[transitionDuration] = 0
        this.$refs.middleL.style.opacity = 1 - this.touch.percent //透明度随percent改变
        this.$refs.middleL.style[transitionDuration] = 0
      },
      middleTouchEnd() {
        //优化：手动滑入滑出10%时，歌词自动滑过
        let offsetWidth
        let opacity
        if (this.currentShow === 'cd') {
          if (this.touch.percent > 0.1) {
            offsetWidth = -window.innerWidth
            opacity = 0
            this.currentShow = 'lyric'
          } else {
            offsetWidth = 0
            opacity = 1
          }
        } else {
          if (this.touch.percent < 0.9) {
            offsetWidth = 0
            opacity = 1
            this.currentShow = 'cd'
          } else {
            offsetWidth = -window.innerWidth
            opacity = 0
          }
        }
        const time = 300
        this.$refs.lyricList.$el.style[transform] = `translate3d(${offsetWidth}px, 0, 0)`
        this.$refs.lyricList.$el.style[transitionDuration] = `${time}ms`
        this.$refs.middleL.style.opacity = opacity
        this.$refs.middleL.style[transitionDuration] = `${time}ms`
      },
      _pad(num, n = 2) { //用0补位，补2位字符串长度
        let len = num.toString().length
        while (len < n) {
          num = '0' + num
          len++
        }
        return num
      },
      //获取初始位置及缩放尺寸
      _getPosAndScale() {
        const targetWidth = 40  //mini-player icon宽度
        const width = window.innerWidth * 0.8 //cd-wrapper宽度
        const paddingLeft = 40
        const paddingTop = 80
        const paddingBottom = 30  //mini-player icon中心距底部位置
        const scale = targetWidth / width
        const x = -(window.innerWidth / 2 - paddingLeft) //X轴方向移动的距离
        const y = window.innerHeight - paddingTop - width / 2 - paddingBottom
        return {
          x,
          y,
          scale
        }
      },
      //控制播放列表
      showPlaylist() {
        this.$refs.playlist.show()
      },
      ...mapMutations({
        setFullScreen: 'SET_FULL_SCREEN',
      }),
      ...mapActions([
        'savePlayHistory'
      ])
    },
    watch: {
      currentSong(newSong, oldSong) {
        if (!newSong.id) {
          return
        }
        if (newSong.id === oldSong.id) {
          return
        }
        if (this.currentLyric) {
          this.currentLyric.stop() //切换歌曲后，清空前一首歌歌词Layric实例中的定时器
          this.currentTime = 0
          this.playingLyric = ''
          this.currentLineNum = 0
        }
        //确保DOM已存在 不使用this.$nextTick，保证手机微信中从后台切回前台时歌曲重新播放
        clearTimeout(this.timer)
        this.timer = setTimeout(() => {
          this.$refs.audio.play()
          //  this.currentSong.getLyric()//测试歌词
          this.getLyric()
        }, 1000)
      },

      playing(newPlaying) {
        const audio = this.$refs.audio
        this.$nextTick(() => { //确保DOM已存在
          newPlaying ? audio.play() : audio.pause()
        })
      }
    },
    components: {
      ProgressBar,
      ProgressCircle,
      Scroll,
      Playlist
    }
  }
</script>


<style lang="stylus" scoped>
    @import "../../common/stylus/variable"
    @import "../../common/stylus/mixin"
    .player
        .normal-player
            position: fixed
            left: 0
            right: 0
            top: 0
            bottom: 0
            z-index: 150
            background: $color-background
            .background
                position: absolute
                left: 0
                top: 0
                width: 100%
                height: 100%
                z-index: -1
                opacity: 0.6
                filter: blur(20px)
            //背景模糊
            .top
                position: relative
                margin-bottom: 25px
                .back
                    position absolute
                    top: 0
                    left: 6px
                    z-index: 50
                    .icon-back
                        display: block
                        padding: 9px
                        font-size: $font-size-large-x
                        color: $color-theme
                        transform: rotate(-90deg)
                .title
                    width: 70%
                    margin: 0 auto
                    line-height: 40px
                    text-align: center
                    no-wrap()
                    font-size: $font-size-large
                    color: $color-text
                .subtitle
                    line-height: 20px
                    text-align: center
                    font-size: $font-size-medium
                    color: $color-text
            .middle
                position: fixed
                width: 100%
                top: 80px
                bottom: 170px
                white-space: nowrap
                font-size: 0
                .middle-l
                    display: inline-block
                    vertical-align: top
                    position: relative
                    width: 100%
                    height: 0
                    padding-top: 80%
                    .cd-wrapper
                        position: absolute
                        left: 10%
                        top: 0
                        width: 80%
                        height: 100%
                        .cd
                            width: 100%
                            height: 100%
                            box-sizing: border-box
                            border: 10px solid rgba(255, 255, 255, 0.1)
                            border-radius: 50%
                            &.play
                                animation: rotate 20s linear infinite
                            //CD 旋转
                            &.pause
                                animation-play-state: paused
                            .image
                                position: absolute
                                left: 0
                                top: 0
                                width: 100%
                                height: 100%
                                border-radius: 50%
                    .playing-lyric-wrapper
                        width: 80%
                        margin: 30px auto 0 auto
                        overflow: hidden
                        text-align: center
                        .playing-lyric
                            height: 20px
                            line-height: 20px
                            font-size: $font-size-medium
                            color: $color-text-l
                .middle-r
                    display: inline-block
                    vertical-align: top
                    width: 100%
                    height: 100%
                    overflow: hidden
                    .lyric-wrapper
                        width: 80%
                        margin: 0 auto
                        overflow: hidden
                        text-align: center
                        .text
                            line-height: 32px
                            color: $color-text-l
                            font-size: $font-size-medium
                            &.current
                                color: $color-text
            .bottom
                position: absolute
                bottom: 50px
                width: 100%
                .dot-wrapper
                    text-align: center
                    font-size: 0
                    .dot
                        display: inline-block
                        vertical-align: middle
                        margin: 0 4px
                        width: 8px
                        height: 8px
                        border-radius: 50%
                        background: $color-text-l
                        &.active
                            width: 20px
                            border-radius: 5px
                            background: $color-text-ll
                .progress-wrapper
                    display: flex //flex布局
                    align-items: center
                    width: 80%
                    margin: 0px auto
                    padding: 10px 0
                    .time
                        color: $color-text
                        font-size: $font-size-small
                        flex: 0 0 30px
                        line-height: 30px
                        width: 30px
                        &.time-l
                            text-align: left
                        &.time-r
                            text-align: right
                    .progress-bar-wrapper
                        flex: 1
                .operators
                    display: flex
                    align-items: center
                    .icon
                        flex: 1
                        color: $color-theme
                        &.disable
                            color: $color-theme-d
                        i
                            font-size: 30px
                    .i-left
                        text-align: right
                    .i-center
                        padding: 0 20px
                        text-align: center
                        i
                            font-size: 40px
                    .i-right
                        text-align: left
                    .icon-favorite
                        color: $color-sub-theme
            &.normal-enter-active, &.normal-leave-active
                transition: all 0.4s
                .top, .bottom
                    transition: all 0.4s cubic-bezier(0.86, 0.18, 0.82, 1.32)
            &.normal-enter, &.normal-leave-to
                opacity: 0
                .top
                    transform: translate3d(0, -100px, 0)
                .bottom
                    transform: translate3d(0, 100px, 0)
        .mini-player
            display: flex
            align-items: center
            position: fixed
            left: 0
            bottom: 0
            z-index: 180
            width: 100%
            height: 60px
            background: $color-highlight-background
            &.mini-enter-active, &.mini-leave-active
                transition: all 0.4s
            &.mini-enter, &.mini-leave-to
                opacity: 0
            .icon
                flex: 0 0 40px
                width: 40px
                padding: 0 10px 0 20px
                img
                    border-radius: 50%
                    &.play
                        animation: rotate 10s linear infinite
                    &.pause
                        animation-play-state: paused
            .text
                display: flex
                flex-direction: column
                justify-content: center
                flex: 1
                line-height: 20px
                overflow: hidden
                .name
                    margin-bottom: 2px
                    no-wrap()
                    font-size: $font-size-medium
                    color: $color-text
                .desc
                    no-wrap()
                    font-size: $font-size-small
                    color: $color-text-d
            .control
                flex: 0 0 30px
                width: 30px
                padding: 0 10px
                .icon-play-mini, .icon-pause-mini, .icon-playlist
                    font-size: 30px
                    color: $color-theme-d
                .icon-mini
                    font-size: 32px
                    position: absolute
                    left: 0
                    top: 0

    @keyframes rotate
        0%
            transform: rotate(0)
        100%
            transform: rotate(360deg)
</style>
